Effect of roflumilast on airway remodelling in a murine model of chronic asthma.

BACKGROUND: Airway remodelling is associated with irreversible, or partially reversible, airflow obstruction and ultimately unresponsiveness to asthma therapies such as corticosteroids. Roflumilast is a selective phosphodiesterase-4 inhibitor that has an anti-inflammatory effect in chronic obstructive pulmonary disease (COPD). OBJECTIVE: The objective of this study was to study the effect of roflumilast on airway inflammation and remodelling in a murine model of chronic asthma. METHODS: BALB/c mice sensitized to ovalbumin (OVA) were chronically exposed to intranasal OVA administration twice a week for additional 3 months. Roflumilast was administered orally during the intranasal OVA challenge. A lung fibroblast cell line was used in the proliferation assay. RESULTS: Compared with control mice, mice chronically exposed to OVA developed eosinophilic airway inflammation, airway hyper-responsiveness (AHR), and exhibited features of airway remodelling. Administration of roflumilast significantly inhibited airway inflammation and AHR. Roflumilast also significantly decreased goblet cell hyperplasia and pulmonary fibrosis, which are parameters of airway remodelling. The levels of interleukin (IL)-4, IL-5, and IL-13 in the bronchoalveolar lavage (BAL) fluids were significantly lower in the roflumilast group. In vitro, roflumilast significantly inhibited stem cell factor (SCF)-induced cell proliferation of fibroblasts. The SCF concentration and mRNA expression in a murine model also significantly decreased with roflumilast treatment. CONCLUSIONS: These results suggest that the administration of roflumilast regulates airway inflammation, AHR, and airway remodelling in a model of chronic asthma. The beneficial effects from roflumilast may be related to the SCF/c-kit pathway.

Is there a Relationship between Bone Morphology and Injured Ligament on Imaging Studies and Laxity on Ankle Stress Radiographs?

This study aimed to investigate the relationship between bone morphology and injured ligaments on imaging studies and laxity on ankle stress radiographs in patients with lateral ankle instability. In total, 115 patients who had undergone ankle MRI, ankle radiography, and stress radiography were included. Distal tibial articular surface angle, bimalleolar tilt, medial and lateral malleolar relative length, medial malleolar slip angle, anterior inclination of the tibia, and fibular position were measured on ankle radiographs. Tibiotalar tilt angle and anterior translation of the talus were measured on ankle stress radiographs. Degree of ligament injury was evaluated on ankle MRIs. Multiple regression analysis was performed using the following independent variables: age, sex, and factors significantly associated with ankle stress view on univariate linear regression analysis. Age (p=0.041), sex (p=0.014), degree of anterior talofibular ligament injury (p<0.001), and bimalleolar tilt (p=0.016) were correlated with tibiotalar tilt angle. Fibular position and degree of posterior talofibular ligament injury were factors significantly related to anterior translation of the talus. Differences in patient characteristics might predispose ankle stress radiograph results. Comparison of both ankles on stress radiographs is superior to applying fixed numerical values to the injured side in order to reduce the influence of patient factors.

Reliability and validity of lower extremity computed tomography as a screening tool for osteoporosis.

UNLABELLED: We evaluated the correlation between central bone mineral density (BMD) and peripheral bone attenuation using lower extremity computed tomography (CT). A good correlation was found between lower extremity CT and central BMD suggesting that CT is useful for screening osteoporosis, and that peripheral bone attenuation adequately reflects central BMD. INTRODUCTION: This study aimed to evaluate the reliability and validity of CT as a screening tool for osteoporosis and to estimate the correlation between central BMD and peripheral bone attenuation using lower extremity CT. METHODS: In total, 292 patients who underwent a lower extremity, lumbar spine, or abdomen and pelvic CT scan within a 3-month interval of a dual-energy X-ray absorptiometry (DEXA) examination were included. Following reliability testing, bone attenuation of the L1, L2, L3, L4, femoral head, femoral neck, greater trochanter, distal femur, proximal tibia, distal tibia, and talus was measured by placing a circular region of interest on the central part of each bony region on a coronal CT image. Partial correlation was used to assess the correlation between CT and DEXA after adjusting for age and body mass index. RESULTS: In terms of reliability, all bone attenuation measurements, except the femoral neck, showed good to excellent interobserver reliability (intraclass correlation coefficients, 0.691-0.941). In terms of validity, bone attenuation of the L1 to L4, femoral neck, and greater trochanter on CT showed significant correlations with BMD of each area on DEXA (correlation coefficients, 0.399-0.613). Bone attenuation of the distal tibia and talus on CT showed significant correlations with BMD of all parts on DEXA (correlation coefficients, 0.493-0.581 for distal tibia, 0.396-0.579 for talus). CONCLUSION: Lower extremity CT is a useful screening tool for osteoporosis, and peripheral bone attenuation on lower extremity CT adequately reflects central BMD on DEXA.

Physical characterization and in vitro skin permeation of solid lipid nanoparticles for transdermal delivery of quercetin.

OBJECTIVE: Quercetin, a phenolic compound isolated from plants, can act as an antioxidant to protect the skin from oxidative stress induced by ultraviolet rays. The aims of this work were (i) to compare the physical characterization of quercetin-loaded solid lipid nanoparticles (QSLNs) and (ii) to investigate the enhanced skin permeation of quercetin using QSLNs. METHODS: QSLNs were prepared with a certain amount lipid (palmitic acid) and the different ratio of surfactant (Tween(®) 80) by homogenization and ultrasonification method. RESULTS: QSLNs showed mono-dispersed particle size distribution in the ranges of 274.0-986.6 nm and zeta potential from -50.4 to -29.4 mV. Entrapment efficiency of QSLN was 15.2-46.2%, and their crystallinity index was low (0-18.2%). In vitro occlusion test showed QSLN-2 has the highest occlusive effect due to its smallest particle size (274.0 nm), and through these result, QSLN-2 was selected as the optimum formulation. Transmission electron microscopy (TEM) analysis further confirmed the uniform spherical shape of QSLN-2 particles. Field emission-scanning electron microscope (FE-SEM) analysis and histological observation of hairless rat skin showed that the lipid particles of QSLN-2 formed a fused lipid film and, subsequently, it hydrated the surface of the rat skin. Franz diffusion cell was used to measure in vitro skin permeation of quercetin dissolved in propylene glycol (QPG), QSLN-2 and QSLN-3. The results showed that QSLN-2 (33.5 µg cm(-2) , 21.9%) exhibited higher skin permeability than QPG (6.6 µg cm(-2) , 4.2%) and QSLN-3 (14.2 µg cm(-2) , 9.1%), which was visually confirmed by confocal laser scanning microscope (CLSM) image analysis as well. CONCLUSION: The results suggest that QSLN-2, prepared with a surfactant content of 2%, could be used as useful skin delivery system for transdermal delivery of hydrophobic antioxidants such as quercetin.

Preparation and characterization of W/O microemulsion for removal of oily make-up cosmetics.

OBJECTIVE: In the present study, W/O microemulsions (MEs) were prepared for efficient removal of oily make-up cosmetics and the detergency characteristics were studied. METHODS: The W/O MEs were prepared by mixing of a spontaneous emulsifier, cosurfactant and oil, and solubilizing the mixture during addition of water. The wettability and emulsifying activity were, respectively, evaluated by measuring contact angle and absorbance after preparing a total of 20 samples using three emulsifying systems and seven oils. RESULTS: Based on the results, a lower viscosity of the oil component is favourable for higher wettability, and the lower the viscosity of the emulsifying systems, the higher the wettability of the ME. Except in the case of oleic acid (OA), oils having high polarity showed significant emulsifying activity. The equation describing [detergency(ΔE)=98.1wettability(cosθ)+120.5EAI(emulsifyingactivityindex)-77.1] was derived from the detergency measurement results, and it was verified that the wettability contributed more significantly to the detergency than the emulsifying activity. CONCLUSION: These results suggest that the prepared W/O microemulsions can be utilized as cleaning agents for efficient removal of oily make-up cosmetics.

Enhanced skin delivery of liquiritigenin and liquiritin-loaded liposome-in-hydrogel complex system.

OBJECTIVE: To study the permeation of liquiritigenin (LQG) and liquiritin (LQ) as licorice flavonoids into the skin, we prepared ceramide liposome-in-cellulose hydrogel complex system. METHODS: Liposome-in-hydrogel complex systems were developed by incorporating ceramide liposomes into cellulose hydrogels by the swelling method. We evaluated their physical and chemical properties, encapsulation efficiency and skin permeability using Franz Diffusion Cell. It was visually seen by CLSM images analysis. RESULTS: The ceramide liposome, consisting of biocompatible lipid membranes, remained stable for over 3 weeks. Encapsulation efficiencies for liquiritigenin and liquiritin-loaded liposome-in-hydrogel were 69.39% and 64.71%, respectively. Liposome-in-hydrogel complex systems (LQG: 56.55%, LQ: 66.99%) had greater skin permeability than control (LQG: 4.92%, LQ: 5.30%) or a single liposome systems (LQG: 43.34%, LQ: 48.97%) and hydrogel systems (LQG: 38.21%, LQ: 55.07%). CONCLUSION: Liposome-in-hydrogel system can be a potential drug delivery system for topical delivery of antioxidants such as licorice flavonoids to construct antioxidative skin barrier.

Ankle fractures have features of an osteoporotic fracture.

UNLABELLED: We report the bone attenuation of ankle joint measured on computed tomography (CT) and the cause of injury in patients with ankle fractures. The results showed age- and gender-dependent low bone attenuation and low-energy trauma in elderly females, which suggest the osteoporotic features of ankle fractures. INTRODUCTION: This study was performed to investigate the osteoporotic features of ankle fracture in terms of bone attenuation and cause of injury. METHODS: One hundred ninety-four patients (mean age 51.0 years, standard deviation 15.8 years; 98 males and 96 females) with ankle fracture were included. All patients underwent CT examination, and causes of injury (high/low-energy trauma) were recorded. Mean bone attenuations of the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis were measured on CT images. Patients were divided into younger age (<50 years) and older age (≥50 years) groups, and mean bone attenuation and causes of injury were compared between the two groups in each gender. RESULTS: Proportion of low-energy trauma was higher in the older age group than in the younger age group, but the difference was only significant in female gender (p = 0.011). The older age group showed significantly lower bone attenuation in the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis than the younger age group in both genders. The older age group showed more complex pattern of fractures than the younger age group. With increasing age, bone attenuations tended to decrease and the difference of bone attenuation between the genders tended to increase in the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis. CONCLUSIONS: Ankle fracture had features of osteoporotic fracture that is characterized by age- and gender-dependent low bone attenuation. Ankle fracture should not be excluded from the clinical and research interest as well as from the benefit of osteoporosis management.

The association between the self-perception period of overactive bladder symptoms and overactive bladder symptom scores in a non-treated population and related sociodemographic and lifestyle factors.

AIMS: To investigate the association between the self-perception period of OAB symptoms (SP-OAB) and the overactive bladder symptom score (OABSS), along with related sociodemographic and lifestyle factors. METHODS: This was a cross-sectional study comprised of 192 men aged 40 years and older who participated in a prostate examination survey between February and May 2009 and proved to have OAB. Survey questionnaires included items on the OABSS and the SP-OAB assessed by the OABSS. Various sociodemographic and lifestyle factors were also included. RESULTS: The average SP-OAB period was 24.72 ± 45.75 months and became significantly longer as the severity of OAB increased in correlation analysis (coefficient = 0.501, p < 0.001). Age, education, income, regular check-up, health maintenance and occupation were all risk factors in both OABSS and SP-OAB in univariate analysis. Body mass index (BMI), family size and SP-OAB were risk factors for OABSS in univariate analysis. Age and regular check-ups were factors in both OABSS and SP-OAB in multivariate analysis. BMI, income and SP-OAB were risk factors for OABSS. CONCLUSION: These findings suggest that the SP-OAB is an independent risk factor for OAB progression and that various sociodemographic and lifestyle factors affect OABSS. The self-perception period should be considered in the treatment and prevention of OAB symptoms.

Re-categorisation of male lower urinary tract symptoms based on the international prostate symptom score questionnaire.

AIMS: The purpose of this study was to develop a new sub-classification system for male lower urinary tract symptoms (LUTS)-mild, moderate and severe-using the conventional International Prostate Symptoms Score (I-PSS). METHODS: From October 2007 to March 2012, a total of 2234 male patients (≥ 50 years old) presenting with LUTS were enrolled in this study. Patients were sorted according to their I-PSS (ranging from 1 to 35 points) and divided into three groups based on their quality of life (QoL) score. A chi-square automatic interaction detection (CHAID) algorithm, based on adjusted significance testing, was used. The Kappa coefficient was calculated for the agreement of original and new categorisation. RESULTS: Mean total I-PSS and QoL scores were 11.0 and 2.9 respectively. According to the original classification, 838 patients (38.6%) had mild, 1053 (48.5%) had moderate and 282 (13.0%) had severe symptoms. After the CHAID algorithm was applied, the scores were re-categorised as 'mild' (1-6 points), 'moderate' (7-21 points) and 'severe' (22-35 points). The overall model was able to correctly predict whether an I-PSS was associated with mild, moderate or severe symptoms, with 70.1% accuracy. According to this new classification, 704 patients (32.4%) were shown to have mild, 1255 (57.8%) to have moderate and 214 (9.8%) to have severe LUTS. The agreement of conventional and new categorisation is very strong (Kappa coefficient = 0.84). CONCLUSIONS: Conventional categorisation of LUTS by I-PSS needs to be updated and the category of moderate LUTS should be broadened.

Treatment satisfaction with low-dose tamsulosin for symptomatic benign prostatic hyperplasia: results from a multicentre cross-sectional survey.

AIMS: To evaluate the efficacy and treatment satisfaction with low-dose (0.2 mg) tamsulosin in patients with symptomatic benign prostatic hyperplasia (BPH), and to investigate individual lower urinary tract symptoms according to treatment satisfaction. METHODS: A cross-sectional study was conducted in a total sample of 2574 patients from multiple centres. International Prostate Symptom Score (IPSS), prostate volume, uroflowmetry and combined medications were reviewed. Detailed questionnaires were used to assess treatment satisfaction and IPSS 8 weeks after treatment with low-dose tamsulosin. RESULTS: After 8 weeks of treatment with low-dose tamsulosin, IPSS improved significantly. Among the 2574 patients, 1,630 (63.42%) were satisfied and 940 patients (36.50%) were dissatisfied with low-dose tamsulosin. The reasons for dissatisfaction included efficacy problems (84.66%) and side effects (3.72%). Treatment satisfaction was affected by symptom duration, baseline IPSS, and prostate size (p = 0.0441, < 0.001, < 0.009, respectively). IPSS voiding (IPSS-V) and IPSS storage (IPSS-S) after treatment differed significantly depending on the degree of satisfaction (p < 0.001). IPSS-V after treatment did not improve in patients who were 'not satisfied' or 'totally not satisfied' (p = 0.170, 0.240, respectively). All the individual IPSS items except urgency (p = 0.1436) varied significantly with the degree of satisfaction (p < 0.001). CONCLUSIONS: Treating symptomatic BPH with low-dose tamsulosin improved IPSS, but more than one-third of patients were dissatisfied with the treatment. The main reason for dissatisfaction was efficacy problems, and the degree of satisfaction was related to symptom duration, baseline IPSS, and prostate size, and also to IPSS-V. In patients with severe LUTS, the tamsulosin dose should be increased earlier.

Sociodemographic and lifestyle factors affecting the self-perception period of lower urinary tract symptoms of international prostate symptom score items.

AIMS: This study investigated the influence of sociodemographic and lifestyle factors on the lower urinary tract symptom (LUTS) self-perception period and International Prostate Symptom Score. METHOD: This cross-sectional study examined 209 men aged ≥ 40 years with non-treated LUTS who participated in a prostate examination survey. Questions included International Prostate Symptom Score (IPSS) items with self-perception periods for each item. Sociodemographic and lifestyle factors were also assessed. Participants were divided by mild LUTS (IPSS less than 8) and moderate-to-severe LUTS (IPSS 8 or higher). RESULTS: Self-perception period of the moderate-to-severe LUTS (n = 110) was affected by BMI; the self-perception period of the mild LUTS (n = 90) was affected by age, income, occupation and concomitant disease. Moderate-to-severe LUTS were affected by self-perception period (p = 0.03). Self-perception period was affected by concern for health (p = 0.005) by multivariate analysis, and self-perception period of mild LUTS was affected by BMI (p = 0.012). Moderate-to-severe LUTS were affected by age, number of family members, concern for health and drinking (p < 0.05, respectively) by multivariate analysis. CONCLUSION: Lower urinary tract symptom was affected by self-perception period. In moderate-to-severe LUTS, age, concern for health and drinking were affecting factors of self-perception period.

Health care burden and medical resource utilisation of idiopathic pulmonary fibrosis in Korea.

SETTING: Despite the clinical importance of idiopathic pulmonary fibrosis (IPF), its epidemiology has been rarely reported. The economic burden from IPF is therefore difficult to predict. OBJECTIVE: To analyse the health care burden and current situation with respect to medical resource utilisation in patients with IPF in Korea. METHODS: We analysed nationwide data collected between 2009 and 2013 from the Korean Health Insurance Review and Assessment (HIRA) database. Patients with IPF were defined by the K-J84.18 code of the Korean Classification of Disease, 6th revision. RESULTS: The total direct health care costs increased from US$19 805 167 in 2009 to US$31 410 083 in 2013; the principal factor responsible for the highest proportion of costs was hospitalisation. The proportion of the total IPF patient population who were hospitalised at least once a year was 27.2%, and the average length of hospital stay was 12.7 days. From post-hoc analysis, hospital admission, emergency room visit and intensive care unit admission rates showed significant seasonal variations; the admission rates were highest in the spring and lowest in autumn. CONCLUSIONS: Health care costs of IPF are increasing annually, with hospital admissions representing the major financial burden.

Reliability of classification of ring and little finger carpometacarpal joint fracture subluxations: a comparison between two-dimensional computed tomography and three-dimensional computed tomography classifications.

The aims of this study were to develop a classification for ring and little finger carpometacarpal joint fracture subluxations based on three-dimensional computed tomography images and evaluate the inter- and intraobserver reliability of the three-dimensional computed tomography classification. A retrospective review was performed of 30 cases of ring and little finger carpometacarpal joint fracture subluxations from 2005 to 2013. We classified ring and little finger carpometacarpal joint fracture subluxations into three types based on three-dimensional computed tomography images. An orthopaedic surgeon with 2 years of experience, a consultant hand surgeon with 8 years of experience, and a consultant radiologist with 9 years of experience, who were completely blind to the treatment algorithm, evaluated 30 cases twice at a 2-week interval using our new classification based on three-dimensional computed tomography images and the other classification based on two-dimensional computed tomography images. Our three-dimensional computed tomography classification showed almost perfect interobserver and intraobserver reliability and resulted in a better level of agreement than two-dimensional computed tomography classification.

Oral administration of collagen conjugated with cholera toxin induces tolerance to type II collagen and suppresses chondritis in an animal model of autoimmune ear disease.

B10.RIII (H-2r) mice were orally administered cyanogen bromide peptide 11 (CB11) or cholera toxin B (CTB)-conjugated CB11 to induce tolerance in collagen-induced autoimmune ear disease. Oral administration of a high dosage of CB11 provided partial protection from chondritis. However, administration of a tiny amount of CTB-CB11 conjugate effectively suppressed chondritis. Oral administration of CTB-CB11 conjugate did not alter the stimulation of T cells in vitro or the fine specificities of B cells. The oral administration of CTB-CB11 caused a higher level of type II collagen-specific IgG and its subclass. Interestingly, increases of TH1 cytokine (interferon-gamma) in Peyer's patches and of TH1/TH2 cytokines (interleukin-2 and interleukin-4) in lymph nodes were detected in mice that had been fed CTB-CB11. An increase of CD8+ T cells in the Peyer's patches with a decrease of CD8+ T cells in lymph nodes was seen in mice that had been fed CTB-CB11. These results suggest that protection from chondritis by oral administration of minute amounts of CTB-CB11 conjugate can be achieved by a mechanism distinct from that of conventional oral tolerance induction.

Proto-oncogene Raf-1 as an autoantigen in Meniere's disease.

The 28 kd protein extracted from the guinea pig inner ear membranous fraction, which reacted with sera from patients with Meniere's disease, has been subjected to microsequencing. Nineteen amino acids were obtained (IVQQFGFQRRASDDGKLTQ). A protein data bank search showed that this sequence corresponded to residues 41 to 60 of human Raf-1 protein. Sera from 16 of 27 patients with Meniere's disease showed reactivity to the recombinant purified glutathione-S-transferase-Raf-1 protein. These results support the hypothesis that a subgroup of patients who suffer from Meniere's disease, as well as some other kinds of autoimmune inner ear diseases, have an autoantibody against Raf-1 protein.

Presence of autoantibodies in the sera of Meniere's disease.

We examined the sera of patients with Meniere's disease for the presence of antibodies against 8 inner ear antigens by enzyme-linked immunosorbent assay (ELISA). One hundred eight patients with Meniere's disease and 28 control subjects were studied. The antibodies against chicken type II collagen, bovine type II collagen, the cyanogen bromide cleaved peptide 11 (CB11) of each, type IX and XI collagens, C-Raf, and tubulin were measured by ELISA. The sensitivity of each antigen was between 37% and 60% individually, and was 91% when all 8 inner ear antigens were combined. These results showed that 91% of Meniere's disease sera have antibody activities to 1 or more of these inner ear antigens. The results suggest that performing ELISA for these 8 inner ear antigens was useful as a diagnostic tool for Meniere's disease. Further study is required for elucidating the role of these antigens in the pathogenesis of Meniere's disease, which might eventually result in better therapy.

The effect of vaccination with DNA encoding murine T-cell epitopes on the Der p 1 and 2 induced immunoglobulin E synthesis.

BACKGROUND: Immunization with naked plasmid DNA leads to strong and persistent cell-mediated and humoral immune response to plasmid encoded antigen. Vaccination of DNA encoded whole allergen has been tried, but little information is currently available on the efficacy of DNA encoding T-cell epitopes in allergic disease. The purpose of this study was to determine whether the vaccination of naked plasmid DNA encoding only T-cell epitopes suppresses the allergic reaction as effectively as naked DNA encoding whole segments of allergen. METHODS: We immunized mice with a mixed naked plasmid DNA encoding the five classes of murine T-cell epitopes on Der p 1 and Der p 2 three times at weekly intervals via an intramuscular injection of BALB/c mice. Control mice were injected with the pcDNA 3.1 blank vector. After 3 weeks, the mice were actively sensitized twice and allowed to inhale the Der p extracts intranasally six times at weekly intervals. RESULTS: The vaccinated mice showed a significant attenuated induction of Der p-specific immunoglobulin E synthesis compared to controls. In terms of the Der p-specific IgG2a antibody response, the vaccinated mice showed more prominent responses than the control mice group. In addition, analysis of the cytokine profile after Der p stimulation of the lymph-node cells revealed that the level of the mRNA expression of the interferon-gamma gene was higher in the vaccinated mice than in the controls. Histologic studies showed a much reduced infiltration of inflammatory cells in lung tissue of the gene-vaccinated mice in comparison with the controls. CONCLUSIONS: These results suggest that vaccination with DNA encoding T-cell epitopes effectively inhibits allergen-induced IgE synthesis and reduces cell infiltration in lung tissue. Thus, gene therapy using T-cell epitope-encoding DNA presents an ideal way of combating allergic disease in the future.

Molecular mechanism of autoimmune hearing loss.

Molecules considered as autoantigens in autoimmune sensorineural hearing loss and Meniere's diseases are type II collagens, type IX collagens, 30 kD proteins of inner ear membranes, laminin, 68 kD proteins of inner ear, PO protein, Raf I protein and beta-tubulin are reviewed in relation to molecular mechanisms of autoimmune injury of inner ear resulting in hearing loss.

MR imaging of solitary pulmonary lesion: emphasis on tuberculomas and comparison with tumors.

The aim of this study was to determine whether solitary pulmonary tuberculoma and malignant tumor can be differentiated on the basis of magnetic resonance (MR) signal intensity. Twenty-eight patients with solitary pulmonary lesions were prospectively studied with MR imaging: T1-weighted, enhanced T1-weighted, proton density-weighted, and T2-weighted spin echo images were obtained. The confirmation methods used were computed tomography (CT)-guided biopsy in seven patients with lung cancer and four patients with tuberculosis; surgery in ten patients with lung cancer and five patients with tuberculosis; and laboratory data in two patients with tuberculosis. Morphologic features and MR signal intensity were examined in detail. As the test for detection of tuberculoma, signal difference on T2-weighted images was carefully analyzed. The signal intensity ratio of the nodule to thoracic muscle signal intensity was measured. The signal intensities obtained from the lung cancers and tuberculomas were variable on pre-and post-enhanced T1-weighted images and proton density-weighted images. Masses were hypointense in 2 of 17 patients with lung cancer and in 9 of 11 patients with tuberculoma on T2-weighted images (sensitivity 82%, specificity 89%, accuracy 87%). The mean signal intensity ratios of the tuberculomas to muscle were significantly lower than those of malignant tumors on T1-weighted, enhanced T1-weighted, proton density-weighted, and T2-weighted images (P < 0.0001). After gadolinium-DTPA enhancement, 2 malignant tumors and 7 tuberculomas showed a marginal rim enhancement pattern, whereas 15 malignant tumors and 2 tuberculomas revealed a diffuse enhancement. The results of MR imaging were consistent with those of CT in 84% of the patients. MR imaging is a helpful adjunctive method in terms of differentiating a tuberculoma from a malignant tumor.